Assessing clinical and psychological features: who are patients showing a nocebo reaction during the drug challenge test?

The nocebo reaction, namely the undesirable effect of an inert substance (placebo), is a phenomenon rarely investigated in literature. A better knowledge of this reaction may help clinicians in the management of these patients in clinical practice. Patients with drug adverse reactions (ADR) undergoing the drug challenge test are an ideal model for studying the nocebo effect, and the study aims to investigate their clinical and psychological features. One hundred and twenty patients (M-age = 4659, SD = 15.5; 82% female), of which 90 non responders and 30 with nocebo reactions (25%) were recruited, and completed a battery of psychological measures: State-Trait Anxiety Inventory X1-X2, Beck Depression Inventory II, Symptoms Checklist-90-R, Difficulties in Emotion Regulation Scale, Toronto Alexithymia Scale. Clinical features (individual characteristics and ADR clinical history) were collected by clinicians. The results show that older age (p = 0.002), low level of education (p = 0.039) and a depressive tendency (p = 0.030) appear to be potential risk factors for nocebo effects. Although none of the features related to the previous clinical history appear to represent a risk factor for the nocebo reactions (p > 0.05), significant correlations between some of the clinical and psychological characteristics considered (p values from 0.005 to 0.042) help to better delineate the profile of these reactive patients. A specific training of the sanitary team about psychological aspects is recommendable.